It was a rare blowout for the AFC North-leading Ravens, who won their previous five games by a total of 23 points.

Asked how such a thing could happen, coach John Harbaugh replied, ‘‘I have no answer for that. Sometimes it just goes that way, right? Our guys made some plays.’’

Quite a few, actually. The Ravens (7-2) scored on six of their first seven possessions, special teams contributed two touchdowns, and Torrey Smith caught TD passes of 47 and 20 yards.

Flacco and the resurgent Baltimore offense made it look easy against the struggling Raiders (3-6), who have yielded at least 40 points in two straight games for the first time since 1962. The 55 points tied an Oakland record for most allowed, set in 1961 and matched in 1981.

‘‘We had too many mental errors on defense, gave up too many big plays, we turned the ball over too many times and we didn’t execute on special teams,’’ Raiders coach Dennis Allen said. ‘‘When you do those things, it generally results in something like that.’’

Baltimore led, 27-10, at halftime. In the third quarter, Smith scored twice and holder Sam Koch scored on a fake field goal to make it 48-17.

In the fourth quarter, Jones scored on a kickoff return for the second time this season for a 55-20 lead. Baltimore’s previous record for points in a game was 48, against Detroit in December 2009.

‘‘Obviously, we had success,’’ said Flacco, who also ran for a score. ‘‘We ran the game plan and it worked well. We stuck with it. We scored points early and continued to score them.’’

Baltimore has 15 straight home wins, the longest current streak in the NFL.

Carson Palmer went 29 of 45 for 368 yards and two touchdowns for Oakland. He was mercifully pulled in the fourth quarter.

Playing without injured running backs Darren McFadden and Mike Goodson, the Raiders gained only 72 yards on the ground.

Baltimore didn’t punt until the third quarter, and even that turned out well. Phillip Adams fumbled the punt, the Ravens recovered, and Flacco promptly threw a touchdown pass to Smith.

Flacco finished 21 of 33 and did not play in the fourth quarter.

Ray Rice ran for 35 yards and a touchdown on 13 carries. He finished the afternoon with 5,034 yards rushing for his career, joining Jamal Lewis as the only players in Ravens history to top 5,000.

The Raiders used a 55-yard pass from Palmer to Darrius Heyward-Bey to close to 20-10 with 1:39 left in the second quarter. It was the ninth straight game in which Oakland scored in the final two minutes of the first half.

But that gave Flacco enough time to add another touchdown before the break. He went 5 for 6 for 73 yards before Rice ran for a 7-yard score.